Orchidaceae – Orchid Family

Displaying a myriad of visually transfixing examples of divergent and convergent evolution, biomimicry, and sexual selection, little can be said about these otherworldly flowers that has not been said before by more experienced botanists. Irregular, diverse, exotic blossoms reflect the environments and pollinators that derive mutual benefit from interacting with members of this group. Orchidaceae is the largest flowering plant family with 763 genera and 28,000 species.[1] This family is so large that its membership makes up 6% to 11% of all seed bearing plants on Earth.[2] The richest diversity of this family live in the tropics, but are present on six continents, found in a wide array of climates, and 285 species occurring in the United States alone.[3]

Orchid flowers are intricate and bilaterally symmetric, with three sepals and three petals. Two petals are alike and the lower petal is usually modified into a lip or, sometimes, even a bulbous pocket (i.e. Pink Lady Slippers or Calypso Orchids).[4] Some species, including in and around the Pacific Northwest, have single flowers, however most have racemose inflorescences displaying many smaller blossoms. Ovaries are inferior and fruit is a capsule full of numerous microscopic seeds. [5]

Spiranthes romanzoffiana – Hooded Ladies Tresses

Species Code: SPRO 

Growth Habit: Herbaceous perennial monocot growing 6 to 30 cm tall.[6]

Leaves: 3 to 6, linear to lanceolate leaves with parallel veins growing 25 cm long by 2 cm wide.[7]

Flowers: 10 to 60, tiny, greenish white to cream colored flowers are arranged in dense, spiraled spikes.[8] Sepals and petals are long and lanceolate, displaying bilateral symmetry, petals converging with the lip to form a hood. Flowers arranged on inflorescence spike horizontally.

Fruits: Produces elliptic capsules.[9]

Ecology: FACW – Facultative Wetland species, found in a range of ecosystems from beach dunes to low elevation wetland prairies, and riparian zones.[10]

Notes: The most commonly occurring Spiranthes in the state of Oregon and the only member of Orchidaceae found in Willamette Valley wetland prairies.

 

 

 

[1] Simpson, M., Plant Systematics 2^nd ed. Academic Press, Burlington, MA. 2010.  224.

[2]  Pillon, Y., Chase, M. (2007). “Taxonomic exaggeration and its effects on orchid conservation”. Conservation Biology. 21 (1): 263-265. 

[3] Elpel, T. J., Botany in a Day: The Patterns Method of Plant Identification. HOPS Press, 2004. 173

[4] Gilkey, H. Handbook of Northwestern Plants, Revised Edition. Oregon State University Press; Corvallis, OR. 2001. 83

[5] Gilkey, H. Handbook of Northwestern Plants, Revised Edition. Oregon State University Press; Corvallis, OR. 2001.

[6] Pojar, J., Mackinnon, A., Editors ) Plants of the Pacific Northwest Coast. Lone Pine Publishing, Vancouver, Canada. 2004.

[7] Meyers, S. Et al. Flora of Oregon. Volume 1: Pteridophytes, Gymnosperms, and Monocots. Oregon State University Press, Corvallis, OR. 2015.

[8] Pojar, J., Mackinnon, A., Ed. Plants of the Pacific Northwest Coast. Lone Pine Publishing, Vancouver, Canada. 2004. 123

[9] Pojar, J., Mackinnon, A., Ed. Plants of the Pacific Northwest Coast. Lone Pine Publishing, Vancouver, Canada, 2004. 123

[10] Flora of Oregon, 330